This "Pre-K for All: Snapshot of Student Learning" report is one in a series designed to provide DOE with information needed to make important policy and programmatic decisions. The study was conducted in the program's inaugural year in order to give the city a snapshot of student learning to improve the services provided and serve as an initial guidepost to ensure the City's efforts are in the right direction. Other reports in the series describe the program's implementation and effects on families. The academic, social, and emotional benefits of high quality pre-K have already been demonstrated by a substantial body of literature. These studies have shown that high quality pre-K is cost-effective and equips children with the cognitive skills needed for success in elementary school and beyond (Campbell, Ramey, Pungella, Sparling, & Miller-Johnson, 2002; Duncan et al., 2007; Heckman, Moon, Pinto, Savelyev, & Yavitz, 2010; McCelland, Acock, & Morrison, 2006; National Early Literacy Panel 2008; Rathbun & Zhang, 2016; Reynolds, Temple, White, Ou, & Robertson, 2011; and Weiland and Yoshikawa, 2013). Therefore, the goal of this study is not to reaffirm these benefits. Instead, this study describes the first cohort of children to participate in the program, with a focus on the skills children had at entry and their growth over the 2014-2015 study period. As such, the study is formative and descriptive in nature--it is designed to inform policy to help maximize child learning and growth. (author abstract)